A connecting flight last month took me through Paris and gave me the chance to spend four days in a city I had not visited for 30 years.
My plan was simple: to use the Vélib, the city's bike-share project, to follow my front wheel, seeing where the bike took me.
Where did it take me? Up and down the Seine, to old bookshops in the Latin Quarter, to the views from Montmartre, to the tourist overrun Eiffel Tower and the Louvre, to cafés in quaint arcades and food markets alongside a canal.
You don't have to go far to find a Vélib (from the words vélo, meaning bicycle, and liberty). The six-year-old project has 20 000 bikes available from 1 800 bike stations located 300m apart.
You sign up online and then use a code to access the bike on a one-day or seven-day pass. Longer-term customers get a card that they then simply swipe at the bike station to free up a bike.
You quickly learn, though, that you should give the bike a basic check to make sure you get one in reasonable order.
Not always simple
Adjust the saddle and you're off. But it is not always that simple. The bike-share is popular and if you're not early enough all the serviceable bikes at the station can be gone.
It is a clunky little beast, weighing in at a hefty 23kg, and even though 400 mechanics are employed to keep the bikes running, you can get one with a grating chain or a mudguard that rattles against the tyres.
The dolphin-coloured clunkers come with three gears, a basket and a lock for extra convenience. The cost for me was R350 for multiple use over a three-day period. This compares with a ticket on the metro or underground at €1.70 (R24).
Much of Paris is given over to the bicycle. There are bike lanes everywhere, with their own traffic lights. There are some dedicated lanes earmarked for the sole use of cyclists.
You do see other bikes besides the Vélib, but Vélibs vastly outnumber other varieties.
I asked a Parisian or two about this and was told that they prefer the Vélib to their own bikes as theft is common. The project did not begin well, with 30% of the bikes being stolen or destroyed in the first year, but has grown to be an indispensable part of transport in the city, with 250 000 subscribers, about 10% of Parisians, using the service.
Watching with envy
The Vélib has its issues. You can find stations that have no serviceable bikes and others where there is no free space to return a bike, but I understand that you can download apps that can help with such problems.
There is a lot of punching in of data for the short-term user. I watched with envy as the long-term users arrived at the station and did no more than swipe a card to release a bike.
From humble beginnings in Vienna in 2003, bike sharing has spread to more than 500 cities in 50 countries, according to the Economist. It noted that Europe has the most bike-share schemes but Asia has the largest number of shared bikes, with more than 350 000 in China alone.
The Vélib is a public-private partnership between the city and JCDecaux, an advertising firm that picks up part of its cost in exchange for advertising rights on bus stops and billboards.
Others, notably in London and New York, have negotiated sponsorship deals in which a chunk of the cost is paid for with branding rights on the bike.
"No two bike-sharing business models are alike," the Economist opined, "but for most cities, the point of such schemes is not to make a profit but to reduce congestion, ease parking problems and encourage their increasingly flabby inhabitants to take more exercise."
Study of the economics of bike sharing
I had hoped to find a detailed study of the economics of bike sharing, because it appears to be a low-cost transit solution, but have not been able to track down any such study.
There appears to be consensus, though, that bike sharing is a useful addition to a suite of urban transport solutions, one that adds nicely to the mix and makes its own contribution.
The issue, though, is not to do with economics, but more with the fact that it is a useful option in cities increasingly plagued by gridlock.
Bicycles are now outselling cars in developed economies. The Guardian reported that this has been the case in Europe since 2000.
Safety, of course, is of prime concern. Here the Vélib has had astonishing success, with just six reported deaths in six years, according to a report by Inter Press Service.
This is a remarkably low figure, given that helmets are generally conspicuous by their absence. Perhaps the impressive safety record has to do with French culture, which is famously bicycle friendly.
Showing great respect for cyclists
In my three days of riding around Paris, I was cut off once, by a large refuse truck that should have given way but did not, and likewise by a taxi.
For the rest, both motorists and pedestrians showed great respect for cyclists.
Across the Channel, cyclists have been seemingly dying in droves and London mayor Boris Johnson, who has lent his name to the Boris Bike, London's bike-sharing project, has been criticised for allegedly not caring about the safety of cyclists.
This week, a BBC report on serious injuries and deaths of cyclists noted that six cyclists have been killed in London in the past two weeks.
It found, though, that cyclist injuries and deaths have been falling since the 1980s, expressed as a percentage of miles cycled.
This means that your chances of getting killed are lower, but you'd still not want to be one of the six taken out this month while riding in London.
Call for dedicated cycle lanes
The call now is for dedicated cycle lanes that are too narrow for cars to use.
In South Africa, Cape Town has shown the lead in developing cycle lanes and has put 400km of lanes in place as part of a 2 000km network it intends to roll out.
The city is also reportedly studying the feasibility of setting up its own bike-share scheme.
Johannesburg plans to create a 5km cycle lane in Noordgesig in Soweto, and a 15km lane between the universities of Johannesburg and the Witwatersrand.
Sandton, meanwhile, is so gridlocked at times that the existing road infrastructure is being rethought, with cycle lanes as one of the options.